Recovery of drill cuttings from subsurface earth formations



Jan. 21, 1964 w. E. KANADY ETAI. 3,118,510

RECOVERY OF DRILL CUTTINGS FROM SUBSURFACE EARTH FORMATIONS 2 Sheets-Sheet 2 Filed Jan. 18. 1961 FIG. 3.

JAY C. WOODS, '%L

5 WWW A T TORNE Y United States Patent 3 118 510 RECOVERY 0F DRiisL UTTlNGS FROM SUB= SURFACE EARTH FORMATIONS William E. Kanady and Jay C. Woods, Houston, Tex., as-

siguors, by mesne assignments, to Jersey Production Research Company, Tulsa, Okla, a corporation of Delaware Filed .l'an. 18, 196i, Ser. No. 83,458 Claims. (Cl. 175308) This invention relates generally to rotary drilling of boreholes, and more particularly, to the problem of obtaining at the earths surface chips produced during rotary drilling operations.

During rotary drilling of boreholes in the earth, it is the practice to circulate a drilling fluid down the bore of the drill pipe and up the annulus around the drill pipe. The drilling fluid passes out of the bottom of the drill pipe and around the drill bit to coil the drill bit and to remove rock chips from the bottom of the borehole. The chips are carried to the earths surface with the drilling fluid. By capturing chips and analyzing them, geologists have been able to obtain much information about the earth formations penetrated by a bit soon after the chips have been cut. .This technique has been practiced for many years using liquid drilling fluids of high viscosity. However, when either air or liquids of low viscosity (less than 1 centipoise) and low specfic gravity (less than 3) are used as the drilling fluid, it has not been possible to obtain satisfactory earth chips. The drill string acts as a very effective rod mill to pulverize the rock chips during their long journey up the annulus to the earths surface. When air is used as the drilling fluid, only dust rises from the annulus. In view of the known fact that air and low viscosity liquid drilling fluids are effective to increase driling rate and prolong drill bit life in areas where such fluids may be used, it is desirable to have a method of capturing useful chips while drilling with such fluids.

Even when heavy liquids are used as the drilling fluid, cuttings from one formation tend to become mixed with cuttings from other formations above or below the one formation. For example, consider a group of cuttings that start the trip up the annulus together. Since the drilling fluid flow in the annulus is frequently laminar, the cuttings in the center of the annulus travel faster than those near the boundaries. Therefore, a cutting which finds itself in the center of the annulus may overtake cuttings from another formation which happen to be traveling near the edge of the annulus. Moreover, the cuttings are generated in a variety of sizes. In laminar flow the cuttings tend to fall or slip back through the drilling fluid with a velocity that can be approximated by Stokes law. This means that small cutitngs have a faster average velocity than large cuttings, so that small cuttings from one formation may overtake large cuttings from another formation that was drilled earlier. Hole irregularities which always exist tend to add to this confusion of cuttings. The net result is that a geologist cannot be certain of the origin of the cuttings that he recovers at the surface.

The present invention contemplates the use of a drill stem havin a pair of interconnected drill stem sections adapted for limited telescoping movement and connected together for rotary driving relationship. The diameter of the lower drill stem section is substantially greater than that of the upper drill stem section, so that the velocity of fluids passing upwardly in the annulus therearound is substantially reduced immediately above the lower drill stern section to produce a certain amount of turbulence thereat. (T he bore of the lower drill stem section is provided with a seat, which the lower end of the upper section engages when the two sections are fully collapsed together in a drilling position and thus forms a fluid-tight 'ice continuous bore throughout the vertical axis of the tool. The lower section is also provided with at least one vertical elongated slot or chamber extending from the seat to the top of the section and communicating over at least a portion of its length with the bore of the lower section when the upper section is raised oif the seat. A second seat below the first seat also is provided within the lower drill stem section, on which is supported a cuttings-collecting basket adapted to be lowered through the drill stem. Passage ways in the lower drill stern section around the cuttings basket are provided so that there is no chance of the flow of drilling fluid being substantially impeded by the cuttings basket and any cuttings that may be deposited therein. Cuttings flowing upwardly through the annulus wlil be caught in the turbulent area immediatley above the lower drill stem section, and at least a portion of the cuttings will fall into the elongated slots. When it is desired to deposit the collected cuttings into the basket, drilling is momentarily stopped, pressure is reduced or bled off within the drill string, and the drill string is rotated to the left and raised to lift the upper section off the seat, thus allowing the cuttings to fall past the seat into the basket. This operation may be performed one or more times before the basket is retrieved from the bore of the drill stem.

Objects and features of the invention that are not apparent from the above discussion will become evident upon consideration of the following more detailed description thereof when taken in connection with the accompanying drawings, wherein:

FEG'S. 1A and 1B are partial cross-sectional views of an embodiment of the invention shown in place in a borehole during drilling operations;

FIG. 2 is a view similar to FIG. 1A showing the component parts in the relative positions attained thereby during cutting deposition in the cuttings basket;

FIG. 3 is a view taken along section 33 of FIG. 2;

FIG. 4 is a sectional view taken along section 44 of FIG. 3;

FIG. 5 is a sectional view taken along section 5-5 of FIG. 1A;

FIG. 6 is a sectional view taken along section 66 of FIG. 3; and

FIG. 7 is a fragmentary sectional view of a portion of the apparatus of FIG. 1A.

With reference now to the figures generally, there is shown a portion of a drill stern, including an upper drill stem section 3 connected to the portions of the drill stem thereabove by a collar 5. The lower end of the upper drill stern section 3 projects into the upper end of a lower drill stem section 4, which is connected to a drill bit sub 33. In FIG. 1B, the roller cones 35a of the drill bit sub are shown in drilling position on the bottom of borehole 1.

As illustrated, the upper portion of the lower drill stem section forms a sleeve member, which encloses the lower end of the upper drill stern section. One or more keys 9 project from the enclosed section and operably engage vertical keyways 39 formed on the inner wall of the sleeve member. The keyways are terminated at their upper end by a shoulder 38 and at their lower end by a shoulder 36.

As shown more clearly in FIGS. 3, 5, and 6, the lower portion of the keyways is enlarged so as to form locking recesses 35, which are engaged by the keys 9 when the upper section 3 is lowered until the bottom of the keys 9 engage the shoulders 36, and the upper section is rotated to the right. It will be noted that the upper section 3 encloses the open side of the keyways 39 in such a manner that the keyways are kept substantially free of any but minute particles of foreign matter, such as cuttings. The keyway recesses 35 are substantially the same length as the keys 9, so that when the two are engaged, vertical movement between the two sections is prevented.

The bore of the lower section below shoulders 35 is provided with an annular seat 17', which seats the lower end of the upper section 3, so that when the upper section is seated on seat 17, a fluid-tight continuous bore is provided throughout the vertical axis of the tool. The bore 31 of the lower drill stem section 4 is provided with a shoulder or lugs 29 for receiving and supporting a cuttings basket 27. The cuttings basket 27 is elongated and contains a plurality of small openings therein so as to permit the flow of drilling fluid therethrough when no cuttings are held thereby. One or more by-pass passageways 25 are provided in the lower drill stem section 4 so as to bypass drilling fluid around the cuttings basket when the cuttings basket is partially filled with earth cuttings. Screens 23 may be provided at the upper opening of the passageways 25 into the bore 31 for the purpose of preventing earth cuttings from passing through the passageway.

One or more elongated chambers 3'7 are provided by the upper sleeve member 7 of the lower section. These chambers are provided by the housing forming the keyways 39, the outer wall of the sleeve member, and the enclosed portion of the upper tubular drill stem section. Chambers 37 extend from the seat 17 to the very top of the sleeve member 7, where they are open ended. It will be noted that when the lower end of the member 14 is seated on the seat 17, the chambers 37 are sealed oi from communication with the bore 31 of the lower section below the seat 17. The chambers 37' provide a means for temporarily storing cuttings falling thereinto from the drilling fluid stream passing up the well bore annulus. One or more ports 13 are provided in the lower end of the wall forming the chambers 37. These ports 13 have two purposes. First, when the pipe string is being raised out of the borehole, they function as weep holes to drain any drilling fluid that may be in the chambers 37. The second function is to provide a small flow of drilling fluid down the chambers by virtue of the suction exerted by the drilling fluid flowing therepast up the annulus around the drill stem section 4.

The dett ils of construction of the lower end of upper drill stem section 3 are best shown in FIG. 7. The upper portion of the upper drill stem section 3 may be considered a tubular body member having an annular inner recess 3a at the lower end thereof. A tubular member 14, having an annular flange at the upper end thereof, engages the annular inner recess 3a so as to be in limited telescoping movement with the body portion of the drill stem section 3 and so as to be supported thereby. A coil spring 15 is positioned between the lower end of the body portion of the upper drill stem section 3 and an upwardly facing shoulder 18 on the tubular member 14. An annular sealing means 21 is provided on the lower end of the tubular member 14 so as to seat on the seat 17 to provide a fluid seal between the bore 31 and the chambers 3'7. This arrangement acts as a sort of shock absorber when the upper section 3 is lowered into engagement with the seat 17 and prevents damage to the seat and the seating member 14. As the upper section 3 is lowered with respect to the lower section, the lower end of member 14 and sealing means 21 engages the seat 17 prior to the keys 9 abutting against the lower shoulders 36. Thus, when the two sections are fully telescoped or collapsed, the weight thrust of the upper section is exerted against the shoulders 36, and the member 14 seals against the seat 17 by the bias of the spring 15. This eliminates hanging of the seating member 14 against the seat 17.

During drilling operations the apparatus assumes the position as illustrated in FIGS. 1A and 1B. In this position the keys 9 engage the shoulders 36 and also the keyway recesses 35. The tubular member 14 is biased against the seat 17, so that a fluid-tight bore is maintained throughout the tool for passage of drilling fluid to u, drill bit. The cuttings basket 27 may or may not be positioned as shown at this time. When drilling is commenced, earth cuttings cut by the drill bit 33 are carried upwardly in the annulus by the drilling fluid. These cuttin s are caught in the turbulent area above the lower section and fall out of the fluid stream into the chambers 37.

After a desired drilling interval has elapsed, rotation of the drill string is stopped, pressure is bled off from the bore of the string, and the drill string along with the upper section 3 is rotated to the left to disengage the keys 9 from the recesses 35. The drill string and upper section 3 are then raised until the upper end of keys 9 bang against the upper shoulders 38. This operation raises the seating member 14 oil the seat 17 and allows the cuttings stored in the chambers 37 to fall into the bore 31 and thus into the cuttings basket 27. The basket can then be retrieved by wire line tools lowered through the drill string or can be left to receive more cuttings when desired. As the basket is open ended at the top, a spear grapple or the like may be used to retrieve it. The ratio of the cham er size to the basket may be such that any desired amount of cuttings may be collected before retrieving. When the cuttings have been dumped into the basket, the drill string and upper section are lowered until the keys 9 engage the shoulders 36. Rotation of the drill string to the right engages the keys 9 in the keyway recesses 35. Circulation of drilling fluid is again commenced, and drilling is continued until it is again desired to collect more cuttings in the basket.

The primary purpose of the key locking recesses 35 is to allow the drill stem to be raised when desired without breaking the fluid seal between the sections and also to prevent drillingoil; that is, the lower section moving downwardly relative to the upper section during the drilling operation. Such drilling-oil may occur at times when certain types of formation are encountered that require only a minimum of weight to penetrate.

In order to insure a fairly large catch of cuttings during drilling operations, and also to create the desired turbulence immediately above the lower drill stem section 4, the ratio of the diameter of the lower drill stem section 4 to the diameter of the upper drill stem section 3 should not be less than 1.5. Actually, this ratio should be as large as possible, consonant with good drill string design.

In the above description of the invention, extensive reference has been made to drill stem sections. It is to be understood that this term also includes drill collars and associated subs commonly used in addition to drill pipe to make up a drill string.

The invention makes it possible for a drilling crew to obtain large cutting samples with a minimum amount of labor and very short stoppage of drilling operations. The apparatus is simple, rugged, and virtually foolproof, and is not easily damaged by the rough treatment usually accorded drilling apparatus.

The invention is not necessarily to be restricted to the specific arrangement of parts or procedures described herein, as various modifications thereof may be effected without departing from the spirit and scope of the invention.

The objects and features of the invention having been completely described above, what is desired to be claimed 1s:

1. A tool adapted to be connected into a drill string for collecting earth cuttings from the drill string wcll bore annulus during drilling operations comprising:

upper and lower concentrically arranged tubular drill stem sections interconnected in splined relationship for limited vertical movement relative to each other from a collapsed, driving position to an elongated position;

an annular seating shoulder provided in the bore of said lower section for seating the lower end of said upper section when said sections are in said collapsed position; said lower drill stem section including an upwardly extending cylindrical housing open on its upper end and enclosing the lower end of said upper section;

said housing and said upper section forming a chamber therebetween extending from said seat to the top of said housing, said housing being of substantially greater diameter than said upper section whereby a reduced velocity area is created in said annulus above said housing;

means arranged in said bore of said lower section below said seat for receiving said cuttings from said chamber when said sections are in said elongated position. 2. A tool adapted to be connected into a drill string for collecting earth cuttings from the drill string well bore annulus during drilling operations comprising:

upper and lower concentrically arranged tubular drill stem sections interconnected in splined relationship for limited vertical movement relative to each other from a collapsed, driving position to an elongated position, the bore of said upper section being at least as large as the bore of said lower section;

an annular seat provided in the bore of said lower section for seating the lower end of said upper section when said sections are in said collapsed position;

said lower drill stem section including an upwardly extending sleeve open at its upper end and enclosing the lower portion of said upper section, said sleeve being of substantially greater diameter than said upper section;

said sleeve and said upper section forming a chamber open at its upper end for receiving said cuttings from said annulus, said chamber extending from said seat to the top of said sleeve, whereby when said sections are in said elongated position, said cuttings will fall from said chamber past said seat into said bore of said lower section.

3. A tool adapted to be connected into a drill string for collecting earth cuttings from the drill string well bore annulus during drilling operations comprising:

upper and lower concentrically arranged tubular drill stem sections interconnected in splined relationship for limited vertical movement relative to each other from a collapsed, driving position to an elongated position;

an annular seat formed in the upper end of the bore of said lower section for seating the lower end of said upper section when said sections are in said collapsed position;

said lower drill stem section including a cylindrical housing, open at its upper end and enclosing the lower end of said upper section, said housing being of substantially greater diameter than said upper section so as to form a chamber about said upper section extending from said seat to the top of said housing;

a landing means arranged in the bore of said lower section below said seat for receiving a retrievable tubular cuttings basket, said landing means so positioned whereby when said basket is landed, the top of said basket is below said seat;

passageways formed in the wall of said lower section whereby when said basket is landed, the bore of said lower section above and below said basket is in fluid communication;

locking means in said sections for releasably locking said sections in said collapsed position.

4. A tool adapted to be connected into a drill string for collecting earth cuttings from the drill string well bore annulus during drilling operations comprising:

upper and lower tubular drill stem sections concentrically arranged for vertical movement relative to each other from a collapsed, driving position to an elongated position;

a concentric seating sleeve arranged on the bottom of said upper section in sealing and limited slidable relationship to said section and extending below the lower end of said upper section, spring biasing means connected between said sleeve and said section for biasing said sleeve downwardly;

an annular seat arranged in the bore of said lower section for seating the lower end of said seating sleeve;

said lower drill stem section including a cylindrical housing open at its upper end, said housing concentrically enclosing the lower end of said upper section whereby an annular chamber is formed about said upper section, said chamber being of substantially greater diameter than said upper section and extending to said seat;

means arranged in said bore of said lower section below said seat for collecting said cuttings; and

locking means in said sections for releasably locning said sections in a driving and collapsed position.

5. A tool in accordance with claim 4 in which said sections are each provided with means operably connected therebetween for limiting said relative vertical movement between said sections, said means so positioned whereby when said seating sleeve engages said seat, said spring biasing means is partially compressed before said sections maintain their maximum collapsed position.

References Cited in the file of this patent UNITED STATES PATENTS 1,525,235 Hansen Feb. 3, 1925 1,656,526 Lincoln Jan. 17, 1928 2,376,974 Miller May 29, 1945 2,670,930 Farror Mar. 3, 1954 2,728,553 Edwards Dec. 27, 1955 2,819,038 Echel Jan. 7, 1958 

1. A TOOL ADAPTED TO BE CONNECTED INTO A DRILL STRING FOR COLLECTING EARTH CUTTINGS FROM THE DRILL STRING WELL BORE ANNULUS DURING DRILLING OPERATIONS COMPRISING: UPPER AND LOWER CONCENTRICALLY ARRANGED TUBULAR DRILL STEM SECTIONS INTERCONNECTED IN SPLINED RELATIONSHIP FOR LIMITED VERTICAL MOVEMENT RELATIVE TO EACH OTHER FROM A COLLAPSED, DRIVING POSITION TO AN ELONGATED POSITION; AN ANNULAR SEATING SHOULDER PROVIDED IN THE BORE OF SAID LOWER SECTION FOR SEATING THE LOWER END OF SAID UPPER SECTION WHEN SAID SECTIONS ARE IN SAID COLLAPSED POSITION; SAID LOWER DRILL STEM SECTION INCLUDING AN UPWARDLY EXTENDING CYLINDRICAL HOUSING OPEN ON ITS UPPER END AND ENCLOSING THE LOWER END OF SAID UPPER SECTION; SAID HOUSING AND SAID UPPER SECTION FORMING A CHAMBER THEREBETWEEN EXTENDING FROM SAID SEAT TO THE TOP OF SAID HOUSING, SAID HOUSING BEING OF SUBSTANTIALLY GREATER DIAMETER THAN SAID UPPER SECTION WHEREBY A REDUCED VELOCITY AREA IS CREATED IN SAID ANNULUS ABOVE SAID HOUSING; MEANS ARRANGED IN SAID BORE OF SAID LOWER SECTION BELOW SAID SEAT FOR RECEIVING SAID CUTTINGS FROM SAID CHAMBER WHEN SAID SECTIONS ARE IN SAID ELONGATED POSITION. 